Malignant profile detected by CT angiographic information predicts poor prognosis despite thrombolysis within three hours from symptom onset

Abstract

Objective: A malignant profile of early brain ischemia has been demonstrated in the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution (DEFUSE) trial. Patients with a malignant profile had a low chance for an independent functional outcome despite thrombolysis within 3-6 h. We sought to determine whether CT angiography (CTA) could identify a malignant imaging profile within 3 h from symptom onset.

Methods: We studied consecutive patients (04/02-09/07) with anterior circulation stroke who received CTA before intravenous thrombolysis within 3 h. We assessed the Alberta Stroke Program Early CT Score (ASPECTS) on CTA source images (CTASI). Intracranial thrombus burden on CTA was assessed with a novel 10-point clot burden score (CBS). We analyzed percentages independent (modified Rankin Scale score < or =2) and fatal outcome at 3 months and parenchymal hematoma rates across categorized combined CTASI-ASPECTS + CBS score groups where 20 is best and 0 is worst.

Results: We identified 114 patients (median age 73 years [interquartile range 61-80], onset-to-tPA time 129 min [95-152]). Among 24 patients (21%) with extensive hypoattenuation on CTASI and extensive thrombus burden (combined score < or =10), only 4% (1/24) were functionally independent whereas mortality was 50% (12/24). In contrast, 57% (51/90) of patients with less affected scores (combined score 11-20) were functionally independent and mortality was 10% (9/90; p < 0.001). Parenchymal hematoma rates were 30% (7/23) vs. 8% (7/88), respectively (p = 0.008).

Conclusion: CTA identifies a large hyperacute stroke population with high mortality and low likelihood for independent functional outcome despite early thrombolysis.